Strip working apparatus



INVENTORID Sept. 16, 1969 R. 'r. KLEMPAY 'ETAL STRIP WORKING APPARATUS Filed Aug. 29, 1967 A TTOR/Vk'ff Sept. 16, 1969 'r, KLEMPAY T 3,466,913

STRIP woaxme APPARATUS Filed Aug. 29, 1967 4 Sheets-Sheet 2 I I J l l l i INVENTORfi RAYMOND T KLEMPAT P 15, 1969 R. 'r. KLEMPAY ETAL 3,466,913

STRIP WORKING APPARATUS Filed Aug. 29, 1967 4 Sheets-Sheet www w ww w mmmww mLBflm K 7 m LMA m ON. ME% MK United States Patent "ice 3,466,913 STRIP WORKING APPARATUS Raymond T. Klempay, Brooktield, and Kenneth L. Bandy, Youngstown, Ohio, assignors to The McKay Machine Company, Youngstown, Ohio Filed Aug. 29, 1967, Ser. No. 664,035 Int. Cl. B21d 1/02; Fl6c 19/50 US. Cl. 72-163 9 Claims ABSTRACT OF THE DISCLOSURE Strip working apparatus providing rolls engaged with opposite sides of longitudinally traveling strip in which the rolls on opposite sides of the strip are carried by respective frames and the latter are pivotally connected together to expose the rolls for cleaning or maintenance. The frame pivot axis extends in a direction from strip edge to strip edge and such axis is spaced from the rolls along the path of strip travel and is offset from the latter.

In order to control axial float of a small diameter working roll without impeding its free rotation or causing transverse fiexure thereof, a thrust roller assembly is provided at each end of such roll. Each thrust assembly consists of a pair of thrust rollers engaged with a roll end in diametrically opposed relation and such rollers are tiltably mounted to equalize the radial loads thereon.

Preamble When even the most perfectly made metal strip is wound in a coil, stresses are frequently induced therein which will prevent the strip from lying flat when it is uncoiled. In certain manufacturing operations, it is essential that the stresses aforesaid be removed so that the strip will lie flat when uncoiled. Where the strip is imperfectly made; that is, where it may vary slightly in thickness from edge-to-edge, the problem is considerably aggravated.

In order to cause uncoiled strip material to lie flat, it has long been customary to pass such strip through a device known as a leveler. Such levelers usually provide an undulating path for the strip formed by working rolls extending from edgeto-edge of the strip and engaged with opposite sides thereof. Such rolls flex the longitudinally moving strip back and forth severely enough to reorientate its grain structure and thus achieve the desired result. Since maximum Working of the strip occurs when it is sharply flexed, most levelers utilize rather small diameter working rolls combined with larger diameter backup rolls which support the working rolls. Unfortunately, the number and size of the rolls in most levelers necessitates relatively frequent roll and bearing replacement and, especially when the strip may be dirty or scaley, frequent roll cleaning. While some prior art levelers could be opened to expose the rolls for cleaning and/ or maintenance, such exposure seldom, if ever, resulted in anything approaching optimum accessibility.

It is, therefore, an object of the present invention to provide a leveler for strip material in which the working and backup rolls are quickly and easily exposed for maximum accessibility for cleaning or maintenance without disturbing leveler adjustments.

In certain types of levelers, the working rolls are not mounted in bearings but are allowed to float as the strip is flexed thereover. This type of leveler desirably permits the use of very small diameter working rolls which, however, must be confined against excessive axial movement. While prior art leveler devices have provided a low friction thrust arrangement to limit axial roll movement, such arrangements have not been satisfactory for very small diameter rolls since high axial thrust on the roll 3,466,913 Patented Sept. 16, 1969 can cause the thrust device to flex the roll transversely. Moreover, the roll is not able to flex freely as the strip is drawn thereover because of the force exerted by such thrust devices.

It is, therefore, another object of the invention to provide a thrust device for a very small diameter floating roll in a strip leveler which, while it limits axial roll movement, will neither induce nor impede flexing of such roll These and other advantages will readily become apparent from a study of the following description and from the appended drawings and in the drawings accompanying this specification and forming a part of this application there is shown, for purpose of illustration, embodiments which the invention may assume and in these drawings:

FIGURE 1 is a side elevational view showing a setting in which apparatus of the present invention may find use,

FIGURE 2 is an enlarged, side elevational view of a preferred embodiment of apparatus seen in FIGURE 1, parts on the near side being broken away to show underlying structure,

FIGURE 3 is a top plan view of the apparatus seen in FIGURE 2, parts on the near side being broken away to show underlying structure,

FIGURE 4 is an enlarged side elevational view, devoid of supporting structure, of the rolls used in the embodiment seen in FIGURE 2,

FIGURE 5 is a view similar to FIGURE 2 but showing certain parts in another position for cleaning, replacement of parts or other maintenance operations.

FIGURE 6 is an enlarged view similar to FIGURE 4, but of another embodiment,

FIGURE 7 is a fragmentary sectional view generally corresponding to the line 7-7 of FIGURE 6 but fragmentarily showing adjoining roll-supporting structure,

FIGURE 8 is a fragmentary view similar to FIGURE 7 but showing parts in elevation, and

FIGURE 9 is a fragmentary side elevational view generally corresponding to the line 99 of FIGURE 7.

Detailed description From left to right as viewed in FIGURE 1, there is shown a conventional pay-off reel 10, a conventional drag bridle 11, a leveler 12 of the present invention, a conventional tension bridle 13, and conventional strip processing equipment 14 which requires flat strip.

Metal strip S extends from the pay-off reel 10, through the drag bridle 11, the leveler 12, the tension bridle 13 and to the processing apparatus 14. Since only the lever 12 forms a part of the present invention, the remaining elements seen in FIGURE 1 need not be disclosed in detail; however, it will be understood that the pay-off reel 10 rotatably supports a coil of strip for unwinding, the tension bridle 13 draws the strip through the lever and feeds it to the apparatus 14, while the drag bridle resists strip movement therethrough to maintain a back tension on the portion of the strip extending between the two bridles. In accordance with usual practice, the rolls forming the tension bridle 13 may be suitably driven while the rolls forming the drag bridle 11 may be driven at a slower peripheral speed than the tension bridle, or braked, to exert the desired tension on the strip S.

Turning now to the leveler 12 which is the subject of the present invention and, with reference to FIGURE 2, such leveler is herein shown to comprise a base or lower frame 15 and an upper frame 16. Rotatably carried by the lower frame 15 are working rolls 17, 18, 19, 20 and 21, and rotatably carried by the upper frame 16 are working rolls 22, 23, 24, 25 and 26. Each of the working rolls aforesaid extend transversely of the strip S in a direction from edge-to-edge thereof and are preferably slightly longer than the width of the widest strip to be processed by the leveler. As will hereinafter be disclosed with greater particularity, the strip is adapted to overlie the rolls 17 through 21 and to underlie the rolls 22 through 26, such rolls providing an undulating path of travel for the strip.

Since the working rolls hereinabove mentioned are of relatively small diameter, the radial loads imposed thereon as the strip is drawn thereover would cause roll deflection of considerable magnitude thus rendering the leveler useless for its intended purpose. In accordance with conventional practice therefore, each of the working rolls is supported against deflection by backup rolls as will next appear.

With reference to FIGURE 4, the working roll 17 is nested between backup rolls 17.1, 17.2 in closely spaced, side-by-side relation. Rolls 17.1, 17.2 are preferably coextensive with the working roll 17. Similarly, roll 17.1 is nested between rolls 17.3, 17.4 while 17.2 is nested between the roll 17.4 and a roll 17.5. The entire nest of rolls 17, 17.1, 17.2, 17.3, 17.4 and 17.5 is rotatably carried by the lower frame 15 in a manner later to appear.

Working roll 22, which is spaced laterally of roll 17 in a direction opposite from that of strip travel, is nested between a pair of supporting backup rolls 22.1, 22.2 while the latter are supported by backup rolls 22.3, 22.4 and 22.5. The entire nest of rolls 22, 22.1, 22.2, 22.3, 22.4 and 22.5 is fixedly but rotatably carried by the upper frame 16 as will next be described.

In order to provide maximum clearance between the backup rolls and the strip, the entire roll nests 17, 17.1, etc., and 22, 22.1 etc., are tilted from the vertical as shown. This permits a deeper meshing, of the working rolls 17, 22; that is, a greater vertical overlap therebetween, to thus work the strip to a greater degree.

Because it may be necessary to vary the amount of work to be performed on the strip by the leveler, it is essential that the degree of vertical overlap between the working rolls 17, 22 be adjustable. In the present embodiment, this is effectuated by mounting the entire roll nest 17-17.5 on a slide 27 (FIGURE 2) carried by the lower frame 15 whose movement may be effected by a screw assembly 28. Notwithstanding the tilt aforesaid of the roll nest, it is important that the slide 27 be vertically shiftable rather than shiftable perpendicularly to the tilt of the roll nests.

Firstly, by shifting the slide 27 vertically, a deeper mesh between the working rolls 17, 22 may be obtained without interference between the upper and lower rolls. Secondly, by so shifting the slide, less sensitivity of adjustment is obtained since, as the working rolls are more deeply meshed, they are also moved apart longitudinally of the strip to partially reduce the stress imposed on the strip by the deeper mesh of the working rolls.

Working rolls 18 and 23 are spaced from the rolls 17, 22 in the direction of strip travel; the roll 18 corresponding to the roll 17 and the roll 23 corresponding to the roll 22, and the rolls 18, 23 cooperating in the same manner as the rolls 17, 22 to work the strip passing therebetween. Working roll 18 is supported similarly to roll 17 by backup rolls 18.1, 18.2, 18.3, 18.4 and 18.5, the entire nest of rolls 1818.5 being mounted on a vertically movable slide 29 (FIGURE 2) whose position may be adjusted by a screw assembly 30. Roll 23 is supported by backup rolls 23.1, 23.2, 23.4 and 23.5, all fixedly but rotatably carried by the upper frame 16. As will be evident, the roll nests which include working rolls 18 and 23 are tilted similarly to the roll nests previously described and for the same reasons as heretofore pointed out.

Turning now to the lower working rolls 19, 20 and 21, and to the upper working rolls 24, 25 and 26, such rolls are spaced from the rolls 18, 23 in the direction of strip travel so as to provide a sinuous path through which the strip passes. The upper rolls 24, 25 and 26 are fixedly but rotatably carried by the upper frame 16 while the lower rolls 19, 20 and 21 are rotatably carried by the lower frame 15. The upper rolls 24, 25 and 26 are supported by a nest of backup rolls 31 and 32 all fixedly but ro tatably carried by the upper frame aforesaid while the lower rolls 19, 20 and 21 are supported by a nest of backup rolls 33, 34 all rotatably carried by the lower frame.

In order to vary the mesh between the upper working rolls 24, 25 and 26 and the lower working rolls 19, 20 and 21 to thus vary the degree to which the strip is worked, the rolls last-mentioned, along with their backup rolls, are mounted on a vertically movable slide 35 (FIG- URE 2) whose position may be adjusted by a screw assembly 36.

While the construction thus far disclosed would function satisfactorily, access to the rolls for cleaning, replacement or other maintenance would be difficult and timeconsuming; accordingly, the present construction provides for pivotal connection of the upper frame 16 to the lower frame 15 whereby such upper frame may quickly be shifted from its normal use position seen in FIGURE 2 to its position seen in FIGURE 5 wherein the working rolls of both frames are exposed for inspection, cleaning or the like.

With reference to FIGURES 2 and 3, one end of lower frame 15 is provided with upstanding, hollow pillars 37 which are spaced-apart sufficiently to allow the strip to pass therebetween. Adjacent its upper end, each pillar 37 rotatably supports a stub shaft 38 and, since such pillars and their associated parts are similar, only one is shown in detailed section in FIGURE 3.

Respective stub shafts 38 are in axially aligned relation and project toward each other, while keyed or otherwise affixed to respective projecting shaft ends are cars 39 formed integrally with the upper frame 16. The arrangement is such that the upper frame 16 is pivotable about the aligned axes of shafts 38 from the position seen in FIGURE 2 to the position seen in FIGURE 5.

It should be noted at this time that it is an important feature of the invention that the aligned axes of pivot shafts 38 are positioned sufficiently above the the pass line of the strip material that the upper frame may be disposed in the position of FIGURE 5 without interference with the strip. To accomplish this, the shaft axes are spaced above the strip an amount at least equal to the maximum vertical projection of the upper frame and its associated parts above the shaft axes when the upper frame is in the position of FIGURE 2.

To provide for movement of the upper frame 16 between the positions of FIGURES 2 and 5, each shaft 38 has a pinion 40 secured thereto within respective pillars 37, and, of course, within respective caps 41 suitably secured to respective pillars and in part forming a journal for respective shafts. Disposed vertically within respective pillars 37 and operably engaged with respective pinions are toothed racks 42 whose lower ends are secured to the piston rods 43 of respective fluid cylinders 44.

In operation, if fluid pressure is admitted to the lower ends of cylinders 44, racks 43 will be shifted upwardly to effect clockwise rotation of pinions 40 and the shafts 38, and consequent shifting of the upper frame 16 from its normal operating position seen in FIGURE 2 to its inspection, cleaning or repair position seen in FIGURE 5. On the other hand, if fluid pressure is admitted to the upper end of the cylinders 44, racks 42 will be returned to the positions seen in FIGURE 2 to thus return the upper frame from its position of FIGURE 5 to its position of FIGURE 2.

In order to positively lock the upper frame 16 in its normal operating position seen in FIGURE 2, the lower frame 15 provides a pair of upstanding ears 45, 46 (see especially FIGURE 3) outboard of the widest strip to be processed. The ears of each pair are closely spaced to receive therebetween respective lugs 47 formed as part of the upper frame 16 and each pair of ears and its lug are provided with aligned apertures in which a pin 48 is slidably received. Each pin 48, only one of which is seen in FIGURE 3, is attached to the piston rod of a fluid cylinder 49 for reciprocation therewith.

In the position of parts seen in FIGURE 3, pin 48 and its matching pin, not shown, are positioned to span the ears 45, 46 with the lug 47 disposed therebetween. This, of course, accurately locks the upper frame 16 in the position shown in FIGURE 2.

When, however, it is desired to shift the upper frame to the position seen in FIGURE 5, the fluid cylinders 49 will be actuated to withdraw the pins 48 from the upper frame lugs 47 to thus permit shifting of the upper frame in the manner previously described. When the upper frame is returned to the position seen in FIGURE 2, the fluid cylinders will be actuated to return the pins to the position seen in FIGURE 3 wherein the upper frame is securely locked to the lower frame.

The embodiment of the invention next to be described is similar to that heretofore disclosed and thus only fragmentary details are herein shown.

It will be recalled that the construction previously described and best shown in FIGURE 4 included lower strip working rolls 17, 18, 19, 20 and 21, and upper working rolls 22, 23, 24, 25 and 26, each with associated backup rolls. In the next to be described embodiment, the rolls 17, 18, 22 and 23 are omitted and in their places are substituted the roll structure seen in FIGURE 6.

The roll structure of FIGURE 6 comprises an initial, lower working roll 50, a second, upper working roll 51 spaced in the direction of strip travel from the roll 50, and a third, lower working roll 52 spaced in the direction of strip travel from the roll 51. As herein disclosed, the strip S travels over the roll 50, under the roll 51, and over the roll 52, and to provide a progressively decreasing working stress in the strip, roll diameters progressively increase from roll 50 to 52.

Underlying and supporting working roll 50 against defleetion is a backup roll 50.1 which is in turn supported by backup rolls, or rollers 50.2, 50.3. Disposed on opposite sides of the working roll 50 are a pair of upper, strip guiding rolls 50.4, 50.5 supported against deflection by backup rolls, or rollers, 50.6, 50.7 and 50.8. As herein shown, the strip guiding rolls 50.4, 50.5 are relatively large in diameter compared to the working roll 50 and function to compel the strip to wrap partially about the roll 50 to thus stress the strip.

Roll 51 and its associated rolls 51.1 through 51.8 are similar to but an inversion of the roll 50 and its associated roll 50.1 through 50.8 while roll 52 and its associated rolls 52.1 through 52.8 are in inversion of the roll 51 and its associated rolls.

As will later be disclosed in detail, the rolls 50.1 through 50.3, rolls 51.4 through 51.8, and rolls 52.1 through 52.3 are rotatably supported by a lower frame 15a, which corresponds to the previously disclosed lower frame 15, while the rolls 50.4 through 50.8, rolls 51.1 through 51.3, and rolls 52.4 through 52.8 are rotatably supported by an upper frame 16a corresponding to the previously disclosed upper frame 16. As will appear, the working rolls 50, 51 seat against and float upon backup rolls 50.1, 51.1 and 52.1 respectively and are supported for rotation solely by such backup rolls.

As seen in FIGURE 7, the roll 51.7 is formed of individual rollers in spaced, side-by-side relation rotatably supported by a bracket 53 mounted on the lower frame 15a. The rolls 51.6 and 51.8 are similarly formed of individual rollers similarly supported on the lower frame. Roll 51.2 like roll 51.4, is also formed of individual rollers rotatably supported on the upper frame 16a by a bracket 54 while the roll 51.3 is identical to roll 51.2.

Still referring to FIGURE 7, the roll 51.1 extends between opposite sides of the upper frame 16a and has a reduced diameter end journaled in an angular slide 55 which is secured to the upper frame for limited vertical sliding movement. A tension spring 56 exerts an upward pull on the slide 55 to maintain the roll 51.1 seated in the pocket formed by thhe rollers 51.2, 51.3. Although the opposite end of roll 51.1 is not shown, such opposite end will be supported identically to the roll end herein illustrated. Although not shown in detail, the strip guiding rolls 51.4, 51.5 are supported in a manner similar to roll 511; however, in this case, the slides 57 at respective ends of these rolls are mounted on the lower frame 15a.

Turning now to the working roll 51, it is to be understood that while the latter is pressed against the roll 51.1 by the strip and is supported for rotation by such roll, means are provided to control axial movement of the roll 51, without imparting any material frictional resistance to its rotation and without promoting or impairng fiexure of such roll.

With reference to FIGURES 7 and 9, a bracket 58 having depending spaced ears 58.1, 58.2 is secured to the upper frame 16a. Disposed between the bracket ears 58.1 is a windowed block 59 in which are journaled a pair of rollers 60 in side-by-side, vertically spaced relation on a shaft 61. For minimum friction, rollers 60 are mounted on ball bearings and their peripheries bear against a radially enlarged end piece 62 on the working roll 51. It is important that the rollers 60 be spaced equidistant from the center of roll end piece 62 to insure against the imposition of thrust forces on the roll 51 which might flex the latter. Closing the window in the outer end of block 59 is a sheet metal cover 63 and closing the window in the block inner end is a sheet metal cover 64 which is, however, apertured at 64.1 to provide limited radial clearance over the roll end piece 62.

To maintain equal radial loading on the rollers 60 so as to insure that such rollers will neither eflect nor impede flexure of the roll 51, block 59 has axially aligned, oppositely projecting stub shafts 65 supported by respective bracket ears 58.1 (see FIGURE 9). Such stub shafts are, however, not journaled directly in respective bracket ears but are instead journaled in slide blocks 66 (see also FIGURE 8) slidable in ways 67 formed in respective bracket ears, whereby such blocks have limited move ment in a direction axially of the roll 51. Bridging the ways formed in each bracket ear is a header bar 68 secured in position by capscrews 69. Interposed between each slide block 66 and a recessed bore in a respective header bar 68 is a compression spring 70 which bias the rollers 60 into engagement with the shaft end piece 62.

Although the opposite end of roll 51 has not been shown, it will be understood that the construction seen in FIGURES 7, 8 and 9 will be duplicated at the opposite side of the apparatus in association with the opposite end of the roll. Moreover, it will be understood that an identical construction to that shown and described with respect to roll 51 will be provided at opposite ends of the working rolls 50 and 52; however, in such case, the brackets will be inverted and attached to the lower frame 15a to project upwardly therefrom since the working rolls 50, 52 form part of the lower frame roll arrangement rather than part of the upper frame roll arrangement as does the working roll 51.

In view of the foregoing it will be apparent to those skilled in the art that we have accomplished at least the principal object of our invention and it will be apparent to those skilled in the art that the embodiments herein described may be variously changed and modified, without departing from the spirit of the invention, and that the invention is capable of uses and has advantages not herein specifically described; hence it will be appreciated that the herein disclosed embodiments are illustrative only, and that our invention is not limited thereto.

We claim:

1. Apparatus for working longitudinally moving strip and having working rolls normally extending transversely of the path of strip travel for engagement with opposite sides of the strip, the improvement comprising:

a fixed frame rotatably supporting working rolls on one side of the strip travel path and having portions adjacent to but spaced from respective edges of the strip and extending to the opposite side of the strip travel path,

a movable frame rotatably supporting other working rolls on the other side of the strip travel path and said movable frame having portions extending across the strip but spaced flatwise therefrom,

and pivot means carried by said fixed frame portions and the axis of said pivot means extending in a direction from edge-to-edge of the strip and spaced from said rolls along the path of strip travel, said pivot means connecting said fixed frame portions to said movable frame to provide for pivot movement of the latter from its normal position wherein the rolls supported thereby are directed toward the strip to position wherein such rolls are exposed for cleaning or maintenance purposes,

said pivot means axis being offset in a flatwise direction from the normal path of strip travel an amount no less than one half of the distance between such normal path of strip travel and the further most projection of said movable frame lying between the edges of the strip in the normal position of such frame to provide for pivotal movement of the latter approximately one hundred eighty degrees from its normal position without interference with the strip travel path.

2. Apparatus for working longitudinally moving strip and having working rolls normally extending transversely of the path of strip travel for engagement with opposite sides of the strip, the improvement comprising:

a pair of frames normally disposed in face-to-face relation on respective sides of the strip travel path and rotatably supporting respective rolls thereat,

means providing a pivot axis extending in a direction form edge-to-edge of the strip and being spaced from said rolls along the path of strip travel, said pivot axis connecting said frames together for relative pivotal movement away from face-to-face relation aforesaid to expose the rolls carried thereby for cleaning or maintenance purposes,

a gear rotatable about said pivot axis upon relative frame rotation aforesaid,

a rack operably engaged with said gear,

and a fluid motor for reciprocating said rack to effect rotation of said gear and consequent relative frame rotation aforesaid.

3. Apparatus for working longitudinally moving strip and having working rolls normally extending transverse ly of the path of strip travel for engagement with opposite sides of the strip, the improvement comprising:

a fixed frame rotatably supporting working rolls on one side of the strip travel path and having portions adjacent to but spaced from respective edges of the strip and extending to the opposite side of the strip travel path,

a movable frame rotatably supporting other working rolls on the other side of the strip travel path and said movable frame having portions extending across the strip but spaced flatwise therefrom,

pivot shaft means rotatably carried by said fixed frame portions and secured to said movable frame for unitary rotation therewith,

and means carried by said fixed frame for effecting rotation of said shaft means and consequent pivotal movement of said movable frame away from its normal position wherein the rolls supported thereby are directed toward the strip to position wherein such rolls are exposed for cleaning or maintenance.

4. The construction of claim 3 wherein the portions aforesaid of said fixed frame are hollow, upstanding pilars,

wherein gears are mounted on said shaft means for unitary rotation therewith and are disposed within respective pillars aforesaid,

wherein racks are operably engaged with respective gears and are vertically reciprocable within respective pillars,

and wherein fiuid motors are disposed within respective pillars and are connected to respective racks for effecting reciprocation thereof and consequent pivotal movement aforesaid of said movable frame. 5. Apparatus for working strip moving longitudinally in a generally horizontal path and having upper and lower working rolls normally extending transversely of the path of strip travel for respective engagement with upper and lower sides of the strip, the improvement comprising:

upper and lower frames normally disposed in face-toface relation on respective sides of the path of strip travel path and rotatably supporting respective upper and lower rolls thereat, each working roll forming part of a roll nest which includes backup rolls engaged with respective working rolls to support the latter against deflection and one of said rolls nests being inclined in the direction of strip travel while the other is inclined in the direction opposite strip travel to increase the arc of engagement of said working rolls with a strip while avoiding interference between respective roll nests,

pivot means whose axis extends in a direction from edge-to-edge of the strip and is spaced from said working rolls along the path of strip travel, said pivot means connecting said frames for pivotal movement of said upper frame away from normal face-to-face relation with said lower frame to expose said rolls for cleaning or maintenance purposes,

and means for vertically shifting said lower roll nest to vary the strip-working relationship between said working rolls.

6. Apparatus for working longitudinally moving metal strip and having a relatively small diameter working roll forceably en-gageable with the strip and such roll having means associated therewith for controlling axial movement thereof, the improvement comprising a pair of thrust rollers in spaced, side-by-side relation engaged with an end of said working roll to control axial movement thereof, said rollers being rotatable about an axis perpendicular to the normal axis of said working roll and being disposed in diametrically opposed relation with respect to said working roll axis.

7. The construction of claim 6 wherein said thrust roller axis is tiltable about a pivot axis to equalize the radial load exerted on said thrust rollers despite flexure of said working roll, said pivot axis being normal to said thrust roller axis and intersecting both the latter and said working roll axis.

8. The construction of claim 7 wherein a pair of thrust rollers are disposed at each end of said working roll.

9. The construction of claim 7 wherein said thrust rollers are rotatably mounted on a frame,

wherein said frame has axially spaced aligned stub shafts which form said pivot axis,

wherein each stub shaft is journaled in a block mounted for movement in a direction axially of said working roll,

and wherein said blocks are resiliently biased in a direction to maintain said thrust rollers in engagement with said working r011 end.

(References on following page) References Cited UNITED STATES PATENTS Hanna 72165 Crowson 72 160 X 5 Sendzimir 72242 10 3,260,093 7/1966 Polakowski 72163 7 3,326,026 6/1967 Guillot 72163 MILTON S. MEHR, Primary Examiner US. Cl. X.R. 

